Two-cycle engine



D. BLUMBER'G TWO CYCLE ENGINE Filed Aug. 20, 1943 5 Sheets-Sheet 1 I INVEN TOR DA /0 BL 0445a;

Nov. 5, 1946. BLUMBERG TWO CYCLE ENGINE Filed Aug. 20, 1943 5 Sheets-Sheet 2 MIN WOT

NLQ

' INVENTOR 0/; W0 5/. (M15596 NOV. 5, 1946. BLUMBE'RG 2,41@,477

TWO CYCLE ENGINE Filed Aug. 20, 1943 s Sheets-Sheei L's m N o L 5 a $4 N N m n v.3

h w W a x g I I :1. f 3 m w \A it a g '3 N 1 HI: o R v P n n k N 3 S N g m g m N v F N &

INVENTOR DAV/D BLUMBEEG Now. 5, 1946. v D. BLUMBERG TWO CYCLE ENGINE 5 Sheets-Sheet 4 Filed Aug. 20, 1943 Y INVENTOR D4 V/D B1 UMBEBG ATTORNEY Nov. 5, 1946.

D. BLUMBERG TWO CYCLE ENGINE Filed Aug. 20, 1943 5 Sheets-Sheet 5 v mvam'oz vDA V/D BLUMEEEG v others.

Patented Nov. 1946 TWO-CYCLE ENGINE David Blumberg, Bridgeport, Conn. Application August 20, 1943, Serial No. 499,315

This invention relates to new and useful improvements in internal combustion engines and has particular relation to a two-cycle engine.

Among the objects of the-invention are to provide in an engine of the type indicated means for thoroughly scavenging the engine cylinder of burned gases, means for forming a large explosive charge in the engine cylinder, an engine of simple construction involving but a relatively few parts, and an improved power take-off means for the engine whereby with a number of the engines operating in a bank any on or more may be stopped without imposing a. heavy drag onthe Other objects and advantages will become apparent from a consideration of the following detailed description taken in connection with the; accompanying drawings wherein a satisfactory embodiment of the invention is shown. However, it is to be understood that the invention is not limited to'the details disclosed but includes all 4 Claims. (Cl. 123-51) ends and provided at spaced points with raised .or radial flange-like portions ll, l2, l3, l4, l5

such variations and modifications as fall within engine crank means alone;

Fig. 6 is a quarter section view of the switch controlling energizing of the spark plug;

Figs. '7 through 11 are schematic views showing the various positions of the crank means;

Fig. 12 is a side elevational view of the engine cylinder alone;

Fig. 13 is an elevational view of the block used in mounting the crank means;

Fig. 14 is a similar view but taken at right anglestoFig. 13;

Fig.'15 is a detail elevational view looking at the underside of the engine cylinder as suggested bythe line l5-l5ofFig. 12; and

Fig. 16 is a transverse sectional view taken as along the line IG-l 6 of Fig. 12.

Referring in detail to the drawings the engine ,of the invention is shown as including a onepiece casing or cylinder 10 open through both with the water jacket at the respective sides of I and Hi the purpose of which will appear. The respective ends of the cylinder III are closed by heads I] and I8 bolted or otherwise secured in place. ,An intake port i9 is provided in head I1 and communicating with said port is a fuel sup ply pipe 20. .A valve 2| controls the port l9 and at the proper times is maintained seated by a coil spring 22 disposed about the stem of the valve. Head 18 is provided with an intake port 23 with which communicates a fuel supply pipe 24. A valve 251controls the port 23 and is adapted to be seated at the proper times by a' coil spring 26 disposed about the stem of the valve.

- Members 21 and 28 are disposed in spaced relation about the intermediate portion of the cylinder Ill and are secured against the opposing The members may be in two or more pieces and are bolted, welded or otherwise formed into units and in any similar manner secured tight to-said A water jacket 29 is secured in spaced relation to the main walls of the cylinder- In by being secured to the flanges H--l2 and l5l6 as shown in Figs. 2 and 3. Water supply and return pipes 30 and 3! are shown as connected the central or intermediate portion of the cylinder ill (see Fig.3). I

At the underside of the engine an oil pan 32 may be bolted at 33 to the lower portions of the members-27 and 28 and at such side the members are provided with vflanges 34 having holes 35 for .the passage of anchoring bolts or the like to be used in securing the engine to any suitable base (not shown). A plate 36 is seemed to and between the upper portions of the members 21 and 28 as by bolts 31 and such plate toward each side of the engine has a pin 38 passing therethrough. About each pin is a coil spring 39 bearing at its respective ends against a head 40 0f the pin and a socket provided in the plate and receiving the inner end of the spring.

These pins enter into the starting of the engine as will later appear and the pins are normally held in elevated positions by the springs 39. The heads of the respective pins are engaged by rollers' M on the respective arms 42 and 43 of a. rocker device generally designated 44 (see Fig. 1) pivotally mounted on a bar 45 carried by bearing members or lugs it on the upper side of the plate 36. A manual means 41 is provided for pulling to pivot the rocker 44 on bar 45 to depress the disc 15.

pins 38 against the tendency of the coil springs 39.

Spark plugs 48 and 48 are threaded through thickened cylinder side wall portions 58 and respectively and enter the cylinder toward but spaced from the heads I? and I8. Firing of the plugs is controlled by similar switches 52 and 53 located at the ends of the cylinder and mounted by the heads I! and I8. These switches are normally in open circuit relation and are closed by a firing chamber head as the latter reaches the end of its compression stroke.

Each switch (see Fig. 6) includes a threaded outer metal shell 54 adapted to be screwed into a, tapped hole in the cylinder. Within said metal shell is a body 55 of insulating material mounting a pair of spaced contacts 55 and 51 connected by wires 58 and 58 with binding posts 68 and BI respectively. Such posts are" carried by the body 55 and exposed at the outer end of the metal shell 54. A lead 52 from a battery or the like (not shown) is connected with binding post 68 while a similar lead 63 connects the binding post 6| with the center electrode of a spark plug.

Located Within the metal shell 54 beyond the inner end of the insulating body 55 is a contact or circuit closing means in the form of a head 84 normally held away from contacts 58 and 51 by a coil spring 66. A rod 81 projecting from said head 64 passes out through the shell wall 85 and may be provided with a small head 88 for engagement by a firing chamber head for the closing of the switch to energize a spark plug.

As shown best in Fig. 3 the rod 5! and its head 88 project slightly into the engine cylinder to be engaged by the mentioned firing chamber head at the time above indicated. When so engaged the rod and its head are pushed outwardly of the cylinder I8 and inwardly of the metal shell 54 and the head 84 is moved against the tendency of the coil spring 68 and into engagement with the contacts'58 and 51 closing the circuit through them and thus to a spark plug.

In its opposite sides the cylinder- I8 is provided with longitudinally extending slots 59 in which operate portions of a crank mechanism. The crank mechanism orpower take-oil means comprises a pair of similar means generally designated I8 and II and of which the means 18 is shown alone in perspective in Fig. 5.

Such means includes a crank shaft I2 connected by a web 18 with a. head, shown as a Web 74 and crank 12 are at one side of the disc 75 and extending from the other side thereof in rigid concentric relation therewith is a drive shaft I8. Web I4 is pivotally connected with the disc in eccentric relation thereto as at IT and such'pivotal connection is located intermediate the ends of the web. At its end remote from. the crank I2 the web mounts a roller I8 the purpose of which will be set forth.

As suggested the crank mechanism is duplicated at each side of the cylinder I8 and it is operated or driven by a double piston construction located within the cylinder and generally designated 19. Such construction comprises a pair of piston heads 88 and 8| each in the form. of an annulus and provided with a skirt portion designated 82 and 83, respectively, telescoping at their inner ends as at 84 and provided with side holes receiving the cranks I2.

connected.

Within said ski t portions and about the crank The telescoped portions of skirts 82 and 83 are rigidly arms 12 is a cylindrical bushing 85 received in an annular block 86 having an opening 8 1 therethrough for such bushing. Block 86 has flanges 88 which bear against the inner surfaces or the skirt of piston 8| as best shown in Figs. 2 and 4 and the block is movable as a unit with the pistons. A pair of holes 89 and 98 communicate the opening 81 through the block 88 with the interior of the piston skirts at the respective sides of the block. These openings pass not only through the block but also through the bushing 85.

Inner cylindrical liners 9| and 92 in the skirts 82 and 83 respectively, bear against the flanges 88 ofthe block 86 and such liners toward their outer ends are provided with holes 93 and 84, respectively. When the engine is assembled the free ends of the cranks I2 are in, or substantially in, abutting aligned relation as in Figs. 2 and 4 and through such cranks extends an opening 85. Such opening through radial openings 96 communicates with arcuate channels or grooves 8! in the surface portions of the cranks and which in certain positions are in communication with the respective openings 89 and 98 through the block 86 and bushing 85 entering the cylinder I8 at opposite sides of said block.

Outwardly of the respective pistons 88 and 8| are firing chamber heads 98 and 88. Rigid with the respective heads 98 and 99 are skirts I88 and I8I passing through the pistons 88 and 8|, respectively, and engaged by packing or piston rings I82 as they so pass. At their inner ends the skirts I88 and I8I are provided with annular outwardly enlarged portions I83 and I84, respectively, carrying piston rings bearing on the inner surfaces of the skirt liners 9| and 92, re-

spectively.

Within the skirts I88 and IM are annular members I and I85, respectively, held against shoulders I8I of the skirts by bolts I88 whereby such members have a fixed relation to the heads 98 and 98, respectively, and are movable with such heads and their skirts. Members I85 and I86 are provided each with a valve seat for the valves I89 and I I8 of the respective members and which valves are normally urged toward their seats by. coil springs III disposed about the stems of the valves; Openings H2 communicate the space between the members |85 and I88 and the respective firing chamber heads and within the skirts I88 and IM with the spaces H3 and II3a between the respective pairs of heads but at the outer sides of said skirts.

Through the firing head 98 are one or more passages I I4 communicating the outer side of said head with the space II 5 located centrally of the innenside of such head while a similar passage IIS provides communication between the outer side of the firing chamber head 99 and the space II! at the inner side ofsuch head. A valve including an inverted cup-like part I I9 controls the passages H4 and a similar valve I28 controls the passages II6. These valves are normally held in positions closing the respective passages by coil springs I2I but are adapted to be forced off their seats by pressure to permit of the movement of fuel from the outer to the inner sides of the respective firing chamber heads.

Exhaust ports I22 and I28 in the respective end portions of cylinder I8 communicate with annular passages I24 and I25, respectively, formed by the cylinder flanges I2-I3 and I4-I5 and cover members I26. Suitable exhaust pipes I2'I may be connected with the mentioned'armular mounted by an annulus I29 held in such members by .bolts I29. Each, annulus has a cover plate I39 bolted or otherwise secured thereto and maintaining the mentioned bearing means in place.

In its intermediate portion the bottom wall of the cylinder I9 is provided with a pair of spaced longitudinally extending slots I3I and I32. The spacing of these slots is the same as that of the entrance openings I33 and I39 in the bottom of This movement of firing chamber head 99 results in the Intake valve 25 being drawn open or unseated againstthe tendency of its coil spring and fuel from the supply pipe 29 is drawn into the block 89. Such entrance openings communicate with the respective sides of the block through passages I35 and I39 respectively. Clearly when the entrances I33'and I34 are in registry with their slots air passages are established from the exterior of cylinder I9 to the interiors of the skirts I 99 and IM of the firing chamber heads 99 and 99.

In the operation of the engine assuming the ing or resulting from the firing of the charge in I the space H311.

When the charge is ignited in the space 3a (which space is in the form of an annulus) the piston 8| is forced toward the left while the firing chamber head 99 together with its skirt I9I and member I99 remains stationary. This results in the compression of air in the annular space I31 between the liner 92 and the skirt I9I and, due to the presence of the liner 92 and the skirt of piston 8|. Further at this time air is admitted to the chamber I39 within the skirt I9I through the opening 95 in the crank I2, passage 99 and groove 91, passage 99 and also through slot I3I, entrance I 33 and passage I35.

There being two independent passages for the supply of air to they chamber I39 neither passage need be large and the rapid supply of the required supply of air is assured. As the block 89 nears the end of the piston stroke its entrance I33 moves ofi the end of slot I3I and no further supply of air is obtained from that source. In addition as the crank 12 turns its arcuate groovefill' is moved out of register with the passage 99 closing off the second source of supply of air to the chamber I38 and sealing the latter.

During movement of the piston in the direction indicated a plentiful supply of air is therefore trapped in the chamber I38. Now when the piston head 8| moves past the exhaust port I23 the pressure between said pistonhead and the firing head 99 drops. At such time the compressed air in the space I31 and in the space between the liner 92 and the skirt of the piston head 8i acts on the portion I99 of the skirt of the firing chamber head 99 and such skirt and head together with the memberi99 are moved in the direction of the piston or away from the cylinder head III.

the hole 99, between the cylinder between the head 99 and the head I8. Valve I29 remains seated at this time as there is no pressure to force it inwardly from its seat and it is preferred that the same be held on its seat under a pressure of approximately two pounds. I

As the firing chamber head 99 and its skirt and member I96 are drawn inwardly by the expansion of the compressed air in the chamber I37 the air in chamber I 39 is slightly compressed and forces valve H9 from its seat. The air then escaping under the valve II 9 serves to. scavenge the burned gases from the engine and it is also noted that the downward or inwardly movement 'of the firing chamber head 99 in the manner describedserves to move the burned'gases toward the exhaust port I23. Thus a thorough scavenging of the engine is accomplished. Valve H9 is held on its seat with but a slight pressure, as, for example, two ounces so that the valve readily ogaens to permit of passage of air from chamber When the heads 8i and 99 were moving in the direction just described the head 99 with its skirt and the firing chamber head 98 and its skirt were being moved toward the left as viewed in Fig. 2. 4

This is a compression stroke for the parts to the left of the cranks in Fig. 2 and the piston 89 and firing chamber head 98 move substantially as a unit since the inner ends of the skirt of each is positively moved by the block 99.

In Fig. 2 it will be understood that the space H3 has been scavenged of burned gases and that a charge has been drawn into the space between the cylinder head I1 and the outer side of the firing chamber head 99. Thus the air pressure has been exhausted from the chamber I49 within the skirt I99 and the valve I99 closes. The air mentioned has been drawn into said chamber I99 through passages 95 and 96 and groove 91 and through slot I32, entrance I34 and passage I 36 in the block 89 during the power stroke of piston 99. As the parts start to move the valve H9 remainsclosed during initial movement and until the piston 89 has moved suflicient to close the exhaust port I22.

Pressure builds up on the fuel charge in the space mentioned and forces open the valve I I9 to expose the outer ends of .the passages H9 so that the fuel charge moves through head 98 (valve 2i having now closed) and into the space 9 between the piston 89 and the firing chamberhead 93 and within the skirt I99 and above the member I95 from which space through openings II2 the fuel moves into the space H3. At the end of the stroke the piston construction-has shifted to the extreme left of the cylinder I9 and a charge is ready to be fired at such end while a charge has been drawn into the right hand end of the cylinder and is ready to be compressed and forced into the space 3a between the piston 8i and the firing chamber head 99.

At this time the crank I2 is in the position reverse to that of- Fig. 2 and is in the position of Fig. 3, 7 That is, the cranks have moved from the right hand end to the left hand end of the slots I59. Small valves I92 in thewalls of skirts I99 and IIII serve to prevent the creation of any vacuum in the chambers I37 and I 93 between the skirt HM and the skirt of piston 8| and the skirt I99 and the skirt of piston 89.

thereof. The cranks 12 are moved back and forth in the cylinder slots 69.

Attention is called to the fact that when the piston heads are moved to close the exhaust ports air is trapped between the piston heads and the firing chamber heads and this air is used asan addition to the charge drawn through the intake ports at the respective ends of the cylinder. Thus, while in each instance a large charge is drawninto the cylinder such charge is further increased in volume by the presence of the mentioned trapped air;

During reciprocation of the piston construction as described the cranks 12 are carried back and forth in the slots 69 of the cylinder l0. These cranks are located in eccentric relation to the heads or discs 15 and the shafts l6 and further thepivots l! of the webs of the cranks are in eccentric relation to the discs and shafts. Thus looking'at Fig. 7 the crank position is that of Fig. 2.

As the cylinder construction remains stationary and the piston construction moves toward the left from the position of Fig. 2 the pivot pins ll of the crank webs move upwardly turning the discs I and the cranks move through the centers of the discs (Fig. 8) to the positions of Fig. 9. Then on the reverse stroke of the piston the webs and pivots move downwardly while the cranks move back through dead center as shown in Fig. 10 to the position of Fig. 11 which is the same as that of Fig. 7 the chosen starting position.

When the engine is stopped as by the closing of 16 does not impart movement to the piston constructlon, but results merely in rotation of such shafts, the discs 15, webs l4 and cranks 12 it will be clear that in any arrangement involving a plurality of the engines in a line with their shafts 16 coupled any one or more of the engines may be stopped or may get out of order and stop withoutimposing a large burden on the yet opcratingenginesof the bank.

Having thus set forth the nature of my invention, what I claim is:

1. In a two cycle internal combustion engine, a cylinder and piston construction, a crank means, said crank means including a crank connected with said piston construction for reciprocation thereby, a web connected at one end with said crank, a power take-off shaft, a head on said,

shaft, a pivot connecting said web with said head, and said pivot eccentric to said crank and said shaft and equally spaced from each of them whereby said crank'is in alignment with said power take-off shaft when said piston construction is in a dead center position. A

2. In a two cycle internal combustion engine, a cylinder, a double ended piston construction in said cylinder, a crank means including a crank connected with said piston construction for reciprocation thereby, a web connected at one end with said crank, a power take-off shaft, a head on said shaft, a pivot connecting said web with said head, and said pivot eccentric with said crank and power take-off shaft and equally spaced from each of them whereby said crank is in alignment with said power take-off shaft when said piston construction is in a dead-center position.

3. In a two'oycle internal combustion engine, a cylinder, a double ended piston construction in said cylinder, .a crank.means including a crank connected with said. piston construction for re- 40 ciprocation thereby, a web connected at one end its fuel'supply and the opening of its ignition circuit the piston construction comes toa dead center position bringing the cranks 12 into alignment with the shafts 16 and concentric with them and the discs I5. This is due to the fact that the pins H are located the same distance from the centers of cranks I2 as from the center of the shafts 16.

Now if the pins 38 (Fig. 3) are in their upper positions, on any attempt to start the engine by a cranking action applied to either or both shafts 18 the latter with the discs 15 will merely spin around carrying the pins 11 but not moving the piston construction.

To start the engine the pins 38 are depressed by actuation of the rocker 44 so that such pins are against the rollers 18 of the respective crank webs 14. Now as the engine is cranked .or a turning movement is applied to the shafts 16 the rollers 18 engaging the pins act through the crank webs and shift the cranks laterally moving them out of dead center position and shifting the piston construction. From there on the cranking of the engine proceeds in the usual manner. Since when the engine is stopped turning of the shafts with said crank, a power take-off shaft, a head on said shaft, a pivot connecting said web with said head, said pivot eccentric with said crank and power take-oil shaft and equally spaced from them whereby said crank is in alignment with said power take-off shaft when said piston construction is in a dead-center position, and manually controlled means for moving said piston construction out of dead-center position to disalign said crank and said power take-off shaft to enable cranking of the engine to be accomplished by turning of said shaft.

, struction for reciprocation thereby, a web connected with said crank, a power take-off shaft, a head on said shaft, a pivot connecting said web with said head, and said pivot eccentric with said shaft and crank and equally spaced from each of them whereby said crank is aligned with said shaft when said piston construction is in a deadcenter position and said shaft may be rotated without movement of the piston construction.

DAVID BLUMBERG. 

